by Alina Vey

Introduction

Historical comparison is useful when it is treated as a study of patterns rather than a prediction of outcomes.

The circumstances that preceded the First and Second World Wars were different from one another, and neither can be mapped directly onto the present. Yet both periods reveal how rivalry, military preparation, alliance structures, territorial disputes and failures of diplomacy can interact in dangerous ways.

The question today is therefore not whether history is repeating itself.

It is whether some of the conditions that have historically made escalation possible are appearing again — and, if so, what can be learned before those conditions become irreversible.

That distinction matters.

Comparing the present with 1914 or 1939 does not mean suggesting that another world war is inevitable, or even that the contemporary international system is following an identical path. It means examining the mechanisms through which strategic competition can become increasingly difficult to control.

The danger of the pre-war environment

Wars rarely emerge from a single decision made in isolation.

More often, a series of developments changes the strategic environment. States become more suspicious of one another. Military capabilities expand. Alliances become more important. Governments begin to interpret the defensive measures of others as potential threats.

This creates what is often described as a security dilemma.

One state increases its military capability because it feels less secure. Another state sees that increase as evidence that it may itself be at risk and responds in kind. Each side can therefore regard its own actions as defensive while interpreting the other side’s actions as threatening.

The significance of this pattern is not that it makes war inevitable.

Rather, it can reduce the margin for error.

The more heavily armed and politically divided an international system becomes, the greater the consequences of misunderstanding an opponent’s intentions.

1914: when alliances became part of the crisis

The outbreak of the First World War followed years of great-power competition, military expansion, imperial rivalry and alliance formation.

By 1914, Europe had become divided into competing blocs, while tensions in the Balkans created a setting in which a regional crisis could engage the interests of several major powers.

The assassination of Archduke Franz Ferdinand was the immediate trigger, but the wider system mattered.

Mobilisation plans, alliance commitments, calculations about credibility and fears of strategic disadvantage contributed to a rapidly escalating crisis.

One of the important lessons of 1914 is therefore the danger created when a local confrontation becomes connected to wider strategic commitments.

Once mobilisation began, governments faced increasing pressure to act before their opponents gained an advantage. Military timetables began to restrict political choices, while each additional step made reversal more difficult.

The lesson is not that alliances cause war.

It is that alliances can transform the strategic consequences of a crisis.

1939: a different route to catastrophe

The road to the Second World War developed differently.

Nazi Germany’s territorial ambitions and rearmament progressively challenged the European security order established after the First World War. The remilitarisation of the Rhineland, the annexation of Austria and the Sudeten crisis were among the developments that altered the balance of power before the invasion of Poland in September 1939.

The period also demonstrated the limits of diplomacy when diplomatic agreements are not supported by a durable settlement of the underlying security problem.

Attempts to avoid a wider war through concessions did not prevent further territorial expansion.

The lesson is not that diplomacy itself fails.

Rather, diplomacy has to operate within a strategic environment in which the parties believe that agreements can be maintained and that restraint will not simply create greater vulnerability.

The experience of the 1930s also illustrates another important pattern: security systems can deteriorate gradually.

The final outbreak of war can appear sudden when viewed from the end of the process, even though the strategic environment may have been changing for years.

Russia and Europe today

The contemporary European security environment is fundamentally different from either 1914 or 1939.

Europe is operating in a nuclear age. International institutions are more developed. Economic interdependence is considerably greater, and the existence of nuclear deterrence creates constraints that did not exist in the same form during the two world wars.

At the same time, Russia’s full-scale invasion of Ukraine has produced the most serious conventional interstate war in Europe in decades.

NATO describes the current environment as its most dangerous since the end of the Cold War and identifies Russia’s war against Ukraine, alongside cyberattacks, sabotage and other hostile activity, as part of a significantly changed security environment.

European states and NATO have consequently placed much greater emphasis on deterrence, defence readiness and military resilience.

At the 2025 NATO Summit in The Hague, Allied leaders committed to a long-term defence investment target of 5% of GDP annually by 2035, comprising core defence requirements alongside defence- and security-related investment such as infrastructure and industry.

This is a substantial change in the strategic environment.

It does not, by itself, indicate an intention to wage a wider war.

Military preparation can be intended precisely to prevent one.

The important question is how such preparation interacts with the perceptions and responses of other states.

The return of military preparation

Military preparation is one of the clearest recurring features across periods of major strategic tension.

Before both world wars, states invested heavily in military capability because governments believed that the balance of power was changing or that future conflict was possible.

Europe is again discussing defence in terms of long-term readiness rather than simply maintaining peacetime forces.

NATO is increasing attention to force readiness, air and missile defence, logistics, infrastructure, defence-industrial capacity and the rapid development and adoption of new technologies. The Alliance has also continued efforts to increase defence production and procurement.

On 18–19 September 2026, NATO’s Military Committee met in Copenhagen with the Alliance’s Allied Chiefs of Defence. The meeting focused in part on current security challenges, readiness and the need to maintain credible deterrence and defence.

This is significant when viewed historically, but it must also be interpreted carefully.

The existence of military preparation does not mean that military conflict is inevitable.

Indeed, the stated purpose of deterrence is to make the cost of aggression sufficiently clear that aggression does not occur.

The historical question is therefore more subtle:

At what point can reciprocal military preparation begin to influence the behaviour and assumptions of the states involved?

The more concerning development: the boundary between war and peace

Modern conflict makes historical comparison more complicated because strategic competition no longer takes place only through conventional armies and clearly declared wars.

Cyber operations, sabotage, disinformation, intelligence activity, economic pressure, interference with critical infrastructure and incidents involving drones or military aircraft can take place below the threshold of open warfare.

NATO now explicitly identifies activities including cyberattacks, critical-infrastructure sabotage and other hostile actions as part of the current security environment.

Recent events in the Baltic region demonstrate why this matters.

In September 2026, a NATO fighter shot down a drone in Lithuanian airspace that the Italian defence minister said most probably came from Russia. Other recent drone incidents have also affected or raised concerns across NATO’s eastern and northern members.

At the same time, not every reported incident has ultimately been established as a hostile act. On 13 September, for example, Lithuania reported that a perceived drone sighting which had prompted authorities to respond was subsequently assessed as a flock of birds.

That distinction is important.

The danger is not only the possibility of a deliberate attack.

It is also the possibility that an ambiguous incident is interpreted as deliberate, producing a response that the other side did not anticipate.

This is where the historical problem of miscalculation becomes particularly relevant.

The escalation problem

The most important historical pattern may therefore be cumulative rather than dramatic.

A single military exercise does not create a world war.

A single sanctions package does not create one.

A single border or airspace incident does not create one either.

The danger arises when multiple pressures accumulate: military deployments, competing security guarantees, territorial disputes, economic confrontation, hostile rhetoric, reduced communication and domestic pressure on governments to demonstrate resolve.

At that point, a decision that might once have been reversible can become politically or strategically difficult to reverse.

Leaders can begin to fear that restraint will be interpreted as weakness, while opponents may interpret restraint as an opportunity to press further.

This is one of the reasons the pre-war periods deserve careful study.

The crucial question is not simply how wars begin.

It is how the range of available choices becomes progressively smaller before they begin.

The significance of the Baltic incidents

The recent Baltic developments illustrate this problem without requiring us to assume a particular intention behind every event.

NATO has described recent airspace violations, drone incidents and hybrid activities as tests of Allied resolve, while reaffirming that the Alliance remains prepared to defend its territory.

Russia’s intentions in individual incidents can be disputed, and attribution is not always immediate or straightforward.

That uncertainty is itself strategically important.

When an incident occurs close to a national border or within the territory of an alliance member, decision-makers have to determine very quickly what happened, who was responsible, whether it was intentional and what response is proportionate.

Those decisions can have consequences beyond the original incident.

This is precisely where historical comparison becomes useful.

The lesson of 1914 is not that every contemporary border incident is a precursor to war.

It is that, within a highly interconnected security system, the interpretation of an incident can matter almost as much as the incident itself.

The nuclear difference

There is, however, one fundamental difference that must not be overlooked:

nuclear weapons.

The major powers in 1914 and 1939 did not operate under today’s nuclear deterrence system.

The existence of nuclear weapons creates both additional danger and a powerful constraint. Direct conflict between nuclear-armed states carries consequences that were not present in the same form during the two world wars.

This does not eliminate escalation risk.

It changes its character.

States can engage in intense conventional, technological, economic and political competition while simultaneously trying to prevent direct confrontation.

That makes signalling, communication, attribution and crisis management particularly important.

Nuclear deterrence therefore does not remove the need for diplomacy.

If anything, the consequences of miscalculation make the preservation of diplomatic channels more consequential.

What history can — and cannot — tell us

History cannot tell us that a particular sequence of events will produce another world war.

It cannot provide a timetable.

And it cannot establish that today’s actors will make the same choices as governments did in 1914 or 1939.

What history can do is identify recurring mechanisms.

It can show how alliances can amplify a regional crisis.

It can show how military preparation can generate counter-preparation.

It can show how territorial disputes can become tests of credibility.

It can show how repeated confrontations can make compromise politically harder.

And it can show how diplomatic channels become most valuable precisely when relations are at their most difficult.

These are patterns worth recognising without assuming that the outcome must be the same.

The importance of keeping diplomacy open

There is another reason the present should not be viewed solely through the lens of confrontation:

diplomatic engagement has not disappeared.

In September 2026, Ukrainian President Volodymyr Zelensky said that he and U.S. President Donald Trump had agreed to meet in New York during the United Nations General Assembly, describing ongoing discussions around de-escalation and fundamental security issues.

Whatever the eventual outcome of such efforts, their existence matters analytically.

They demonstrate that military deterrence and diplomacy are not necessarily opposing approaches.

A state may strengthen its defences while maintaining channels through which misunderstandings can be addressed.

Governments can disagree fundamentally while retaining mechanisms for communication.

Military preparedness can coexist with efforts to establish boundaries, reduce accidental escalation and preserve opportunities for negotiation.

The objective is not to ignore aggression or abandon security.

It is to ensure that, even during periods of intense strategic competition, there remains a route away from escalation.

That may be one of the most important lessons of the twentieth century:

preventing war does not depend only on having the power to respond to it.

It also depends on retaining enough diplomatic space to stop a crisis from becoming irreversible.

Conclusion

The temptation when studying history is to search for repetition.

But history rarely offers exact repetition.

The people are different. The technologies are different. The institutions are different. The strategic calculations are different.

What can recur are the conditions that make miscalculation possible.

Rivalry can produce military preparation.

Military preparation can produce counter-preparation.

Alliances can connect regional disputes to wider strategic interests.

Ambiguous incidents can become tests of credibility.

And repeated confrontation can gradually reduce the space available for compromise.

None of this means that the present is 1914.

It does not mean that the present is 1939.

Nor does it mean that another world war is inevitable.

It means that history remains valuable precisely because it allows us to recognise dangerous mechanisms before they reach their final stage.

History does not necessarily repeat itself.

Sometimes, it rhymes.

And perhaps the value of studying those earlier periods is not to predict the next war, but to recognise the moment when preventing one still remains possible.